OLED is a flat light emitting technology which utilizes organic thin films placed between two conductors in order to create light. When an electrical current is applied between the two conductors a bright light is emitted. OLED technology has many implementations, including displays, such as televisions, and has been utilized in solid state lighting (SSL) applications. A primary benefit of OLED technology as compared to previous technologies is that OLED technology is more efficient, requiring less electrical consumption, and also allows for space saving because OLED devices can be made very thin.
It is generally considered that a white OLED device, in order to qualify as SSL, needs to achieve greater than 100 lm with color rendering index (CRI) greater than 70 and operating time greater than 10,000 hours at 1000 cd/cm2. To accomplish this, there needs to be a host material capable of supplying such results. Most host materials in existence have problems with low stability, high charge injection barrier, and imbalanced charge injection and mobilities. All of these problems lead to a high turn-on voltage and short device lifetime. In order to achieve high efficiency, low turn-on voltage, and long device lifetime, it may be helpful to create stable, high mobility, bipolar host materials. Achieving these criteria will allow for the realization of the full commercial potential of organic light-emitting devices.